We have identified and cultured human CNS derived progenitor cells from the human brain. These cells are nestin positive and do not express any other phenotypic marker of differentiation. Upon treatment of such cells with specific factors, these cells can be directed toward lineage pathways that make these cells neurons, astrocytes or oligodendrocytes. We are in the process of studying the genomics of this differentiation and the proteins that are uniquely made during the course of such differentiation. We use viral infection to mark phenotypes of these cells and are able to increase infection or diminish infection depending upon the pathway that these cells are directed toward. Such experiments will ultimately provide valuable insights into the nature of development of the brain and allow a key experimental tool for a large array of studies for cell therapy.